Fair Value Measurements (Details Textuals) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Fair Value Measurements (Textuals) [Abstract]
Other real estate owned measured at fair value	$ 3	$ 11
Write down of Other Real Estate Owned	1	3
Commitment on standby letters of credit	$ 279	$ 297
Fair Value of Assets and Liabilities [Line Items]
Closing ratio	89.00%
Weighted average discount rate	9.60%
Weighted average constant prepayment rate	15.20%
Maximum [Member]
Fair Value of Assets and Liabilities [Line Items]
Weighted average discount rate	15.00%
Minimum [Member]
Fair Value of Assets and Liabilities [Line Items]
Weighted average discount rate	10.00%

Represents the percentage of loans currently in a lock position which management estimates will ultimately close.

No definition available.

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- Definition

Line items represent fair values of assets and liabilities

+ References

No definition available.

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- Definition

Other real estate owned fair value disclosure.

+ References

No definition available.

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107314-111719

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107314-111719

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- References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount of write-down or reserve recognized in the income statement on real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28.FN5)
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule III)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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